In the NBA the goal is the same as it is here, dissuade tanking by forcing teams to be competitive. Putting a minimum spending floor is the only way to force tanking teams to hire players with skill.
In this game player skills are objective, measurable numbers. Even salary is a function of player skills. Why use salary as a measuring tool for competitiveness when player skill is what determines it?
Your goal should be winning, not spending more money than the next team.
"Air is beautiful, yet you cannot see it. It's soft, yet you cannot touch it. Air is a little like my brain." - Jean-Claude Van Damme